Can Swordtails and Goldfish Live Together?

Swordtails and goldfish are among the most popular pet fish choices due to their beautiful colors and shape. The question is, can swordtails and goldfish live together? The answer is yes. With the right care and management, swordtails and goldfish can coexist peacefully.

Let’s learn more about both species of fish and see how we can create a space where they can coexist without any problems.

Can Swordtail and Goldfish Live Together?

As mentioned above, both fish can live together peacefully. However, you have to work on creating the perfect aquarium that’ll fit both their living requirements and differences.

The main difference between the two is that swordtails are tropical fish, whereas goldfish are cold-water fish.

In addition to requiring different water temperatures, you have to take both fish’s dietary needs into consideration. So how will you find that balance? Let’s find out.

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Temperature Preference

When it comes to temperatures, swordtails like warm temperatures because of their tropical nature. The temperature range of the aquarium should be between 65-82F to keep these guys happy.

On the other hand, goldfish prefer to be in a slightly colder environment. Their ideal temperature range is 68-74F.

With that in mind, in order to keep both together in the same aquarium, the water temperature in your aquarium should be anywhere between 68F and 74F.


Good nutrition is essential to keep your fish healthy, so you have to make sure to make the right choices for both your fish.

The good thing is, both of their diets are closely similar, so you won’t have to worry about getting confused or buying different things.

Swordtail Diet

Protein-based nutrients and plant-based nutrients are the best picks for swordtails. Because swordtails are omnivores, a mix of these two will guarantee they stay healthy.

There are multiple options to choose from like bloodworms, daphnia, mosquito larvae, and brine shrimp. Mix with those some plant-based fish food like algae to keep them strong and healthy.

Goldfish Diet

Goldfish can have the same options we mentioned above for swordtails since they’re omnivores as well, so they can share their food.

However, goldfish will need some additions to their diet to stay well-nourished. High-quality goldfish flakes mixed with frozen brine shrimp or a veggie mix will be a great addition to their diet.


Before putting these two together, we have to learn more about their behaviors to make sure they can live together peacefully.

Swordtail Behavior

Swordtails are hardly aggressive with other fish, and they’re known to be peaceful neighbors. They like to explore their environment and be playful with other tank mates, so you’ll find them interacting with goldfish in a friendly manner.

There are only two cases where you’ll find swordtails showing aggression towards other fish. It’s either for mating purposes or to protect their territory.

The first case can happen when the male swordtails outnumber the females in the aquarium. This causes the males to fight each other in order to mate.

As for the second case, swordtails can show aggressiveness if they feel like their space is threatened. The aggression can go toward their fellow swordtails or their goldfish neighbors.

Goldfish Behavior

Like swordtails, goldfish are sociable and peaceful as well. They’re considered even more sociable than swordtails.

They love to interact with their neighbors and spend time around them. Whether their neighbors are of their own kind or a different kind of fish, they’ll show the same friendliness.

Another fun fact about goldfish is that, with time, they can learn to recognize their owners. This leads them to greet their owners with excitement when they see them. It’s very sweet and wholesome.

There’s one important thing you should know about goldfish, though. Despite their friendly nature, they eat whatever is smaller than them.

So if they grow bigger than their swordtail neighbors, they might eat them. So keep an eye out for their growth.

Aquarium Requirements

Because we’re keeping two different kinds of fish together, we have to try and imitate both of their natural habitats. So let’s get to know more about both of their habitats.

Swordtail Tank Requirements

Swordtails require a water pH level between 0 and 8.4, and the hardness level should be around 10 and 15 dH. They also love many kinds of plants like Ferns and Java Moss.

They also need a private space of their own to spend time in. Driftwoods and caves are a good addition to provide them with privacy.

Another thing you should know is that swordtails like to swim around a lot. One swordtail would need a space of 15-gallon tank space.

This means that you’ll need at least a 30-gallon tank to keep multiple swordtails.

Goldfish Tank Requirements

As for Goldfish, they need a water pH level between 5 and 7.5 and the water hardness should be between 5 and 20 dH.

Like swordtails, they also like to have a private space. So anything like caves, big plants, and dense vegetation will be good for them.

They also require a big swimming space, so you’ll need at least a 20-gallon tank for just one goldfish. If you want to keep more than one, you’ll have to increase the tank size by 10 gallons.

It’s also important to note that goldfish aren’t the cleanest and that they produce a lot of waste. So, It’s essential to have a filter in your aquarium.


Both swordtails and goldfish can add a cheerful touch to your home aquarium. With the right care, they can both be kept together without a problem.

Now that we’ve learned about their differences and their living requirements, let’s see how we can keep these two together.

The first thing to keep in mind is not letting your goldfish grow too big. As we mentioned before, if the goldfish are much bigger than the swordtails, they’ll see them as prey and eat them. If you have goldfish that are too big for swordtails, it’s best not to put them together in the same tank.

The second thing to consider is the tank size. You’ll need at least a 30-gallon tank because both fish love to swim around a lot, they need a lot of space.

And lastly, don’t forget to keep the temperature we mentioned before in mind. A temperature of between 68F and 74F will suffice for both.

Good luck!